A cold fresh-air intake sleeve sweats above the ceiling
Cold intake sleeves through humid spaces need insulation/vapor control. Dry the metal, seal air leaks, and wrap the sleeve with the approved vapor-tight insulation detail.
Do not leave a cold outside-air sleeve bare in a humid plenum and expect paint or caulk to stop condensation.
Check
Look for sweating on the exterior sleeve surface.
Check if insulation is missing, loose, or open at seams.
Verify the sleeve carries cold outside air.
Dry the metal before wrapping.
Tape/seal the vapor barrier continuously around corners and supports.
Steps
Look for sweating on the exterior sleeve surface.
Check if insulation is missing, loose, or open at seams.
Verify the sleeve carries cold outside air.
Dry the metal before wrapping.
Tape/seal the vapor barrier continuously around corners and supports.
Say this to your foreman
The outside-air sleeve at [location] is sweating above the ceiling. I checked the wrap and the metal is bare/cold. Do you want it insulated with the project vapor-barrier detail?